Rctor for magneto-electric machines



Patented July 19. I5 3 the rotor for um'rso STATES ROTOR FOR IAGHETO-ELEOTBIC Specification of Letters Patent.

PATENT OFFICE;

: ABSIOR'OB '10 FIRE Patented July 19, 1921.

Application filed lovember 6, 1918. Serial Io. 261,480.

To all whomz't may concern! Be it known that I, Jacques Boiim acitizen of the Swiss Republic, residing at Obach, Solothurn, Switzerland, have invented certain new and useful Improvements in Rotors for Magneto-Electric Machines, of which the following is a specification.

By suitably shaping the pole pieces of eto electric machines it is posible to pro use such a. time course of the induced current as will enable the range of variation qf the point of ignition to be adjusted up to the limits of any desired but limited angle.

The resent invention has for its ob'ect to provide means of attaining a consi erably wider ra of variation of the point of ignition. ith this object the trailing edge of the pole is provided on its side next to the poles of the magnet with a part composed of magnetically conducting material which is separated from the poles by a layer of non-magnetic material. This arrangenlent has the effect that as the edge of the pole trails, that is to say, moves away from the yoke, the number of lines of force passin from the magnet into the yoke is not ret uced suddenly to Zero, but owing to the transmission of lines of force through the magnetically. ennducti part located next the pole, the said num r is first reduced to a medium value which is then gradually diminished to zero.

This resulting retardation of the variation in the number of lines of force causes also a retardation in the diminution of the induced current, whereby it is possible to get of each of its N'and S poles at par 0: am!

a, respectively, composed of magnetically conducting material. These two parts are fixed to a carrier 1 inserted between the two poles and are separated from their respective poles by intermediate air gaps b, and t b.- respectively.

This invention is applicable both to apparatu's comprising stationary pole pieces and to apparatus comprising rotating armatures.

In an ignition generator the combinationwith an induced member comprising a yoke and spaced pole pieces of magnetic material of an inducing member positioned between said pole pieces and relatively movable thereto and having magnetically polarized projections equal in number to the pole piecesand auxiliary pole tips of magnetic material located on the trailin edges of the rotor poles and magnetically insulated therefrom, whereb the reluctance of the flux path is gradua ly varied during the revolution of the rotor.

In testimony whereof I have signed my name to this specification.

JACQUES BOHLI. 

